Mobile ad hoc wireless networks are vulnerable to active attacks by malicious nodes thanks to their open multiple access medium. These malicious nodes (or attackers) could degrade network performance and even deny legitimate nodes of service. For example, a malicious node may drop or tamper with routing control messages to cause erroneous packet delivery or degrade packet forwarding efficiency. A malicious node may also drop or tamper with user data packets to cause otherwise unnecessary packet retransmissions, such that the network could be overloaded with deliberately injected transmission overhead.
Security protection of a mobile ad hoc wireless network is particularly challenging due to mobility of both friendly and malicious nodes. Cryptographic methods can be used to strengthen data privacy and access control, but are unable to protect the network from malicious mishandling of packets. It would be beneficial if upon detecting an intrusion by a malicious node, a friendly node would alert other friendly nodes such that they could adapt their routing behavior to prevent/nullify future attacks by the malicious node. Therefore, a need exists for a method and apparatus for alerting nodes of a malicious node in a mobile ad-hoc communication system.